The redial function offered on telephones advantageously allows a user to return to a connection that the user previously had or tried to obtain without having to spend the time, effort, and memory to program the number into the telephone. For instance, the user may want to dial a friend staying at a hotel. The friend provided a telephone number and extension. The user can dial the phone number and, after the hotel's telephone system answers, dial the friend's extension.
Unfortunately, the redial function is unable to remember the pause between the telephone number and the extension. When the user attempts to use the redial function, the telephone dials the entire string, the telephone number and the extension, in a single series of tones without a pause to wait until a successful connection is made to the hotel's telephone network and the hotel's telephone network is ready to receive the extension. Further, if the hotel's telephone system receives part of the extension, it may wait for the remaining digits from the user and when the user tries to enter the extension, the hotel's telephone system may incorrectly interpret the first couple digits as the remainder of the extension and connect the user with the incorrect room.
On the other hand, the hotel's system may not receive any of the extension digits. The user may then dial the extension after the hotel's telephone system is ready to receive the extension. Similarly, the redial function offers very little help in situations wherein a sequence of phone numbers are dialed, the dialing of each subsequent number being predicated upon successful connection to intermediate nodes.